Rotatable contact-breaker for magnetos and other purposes.



E. 1. PILBLAD. v ROTATABLE CONTACT BREAKER FOR MAGNETOS AND OTHERPURPOSES. APPLICATION FILED MAR. 10. I917- 1,241,273. PatentedSept.25,1917.

' 1 129.1 \\\\\\\g a H 5/ 1 $1 F A I K Q) B 2/ 6 "617165-563 Fa Men/07"UNITED STATES PATENT. oEEioE.

ERIC JULIUS PILBLAD, or EIcEs'rEE, ENGLAND, Ass'IGN'oE T0 IMPERIAL TYPE-JErrEEooMrAnY, LIMITED, 0E LEICESTER, ENGLAND.

ROTATABLE CONTACT-BREAKERronivmcnEros AND OTHER PURPOSES.

1,241, 2vii T0 aZZ w hU-m it may concern:

Be it known that 1, ERIC JULrus PILBLAD, a subject of the King ofEngland, residing at Leicester, in England, have invented certain newand useful Improvements in Ro tatable Contact-Breakers for Magnetos andother Purposes, of which the following is a specification. 1

This invention relates to magneto con-' tact-breaker devices of the typewherein the contacts are carried on a rotating spindle and one contactis connected to the spindle by an arm which bears against a stationarycam whose operative face is shaped to move the arm axially relatively tothe spindle to efiect the break in the circuit. It is a dis-. advantageo1, contact-breakers as at present commonly used, that the surfaces ofthe co'ntact-points are so difficult of access formspection, cleaningand adjustment; it is the prime object of the present invention toprovide a construction of contact-breaker, such that the workingsurfaces of the contact-points shall be readily accessible forinspection etc.

According to the present invention, a magneto contact-breaker. deviceofthe type described, is characterized by. having the arm which carriesthe movable contact so connected to the spindle that it can be readilymoved from its operative position in such a manner as to carry.onecontact away from in front of the; other to render both working faces ofthe contact readily visible and accessible. 1

Conveniently, according to this invention, the arm carrying the movablecontact is hinged to a part connected with the spindle, and displaceablelocking-means are provided for maintaining the arm in the operativeposition. The locking-means may take the form of a resilientfinger whichnormally constitutes the resilient control for the operative end of thearm, but which is pivotally mounted on the spindle so as to be movableabout its pivot to a position where it permits the said operative end tobe swung away from the cam.

One embodiment of the present invention is illustrated in theaccompanying drawings in .which- Figure'l is a central verticallongitudinal Specification of Letters Patent. Patented Sept, 25, 191Application filed March 10, 1917. Serial No. 153,919.

section of the complete magneto, but showing the contact-breaker devicein elevation;

Fig. 2 is a longitudinal section on the line 2-2 of Fig. 3 to a largerscale. than that of Fig. 1 of the parts constituting the contact-breakerdevice and of some adjacent parts;

Fig. 8 is an end elevation of a detail, and

Fig. 4 is a side elevation ofthe parts shown in Fig. 3,.but with themovable concontact swu'ngaw ay for inspection.

The contact-breaker device comprises an inner contact-carrying disk Acarried onfia tubular spindle B, keyed at B into the spindle O of themagneto armature. Mount ed upon the disk A, but electrically insir latedfrom it, is anxouter disk D which serves to carry the outer contact, notdirectly. but upon a hinged arm as hereinafter described. Thedi-sk D hastwo lugs D upturned from the general plane of the disk,

which support a pivot pin Upon the pivot pin E is mounted the arm whichcar rice the outer contact, this arm being in the form of a disk F thatis centrally apertured and that is provided with three cam. Just at thebase of the finger F is mounted the movable contact H which cooperateswith the fixed contact H mounted upon the inner disk A. The aperture inthe disk F is shaped in the manner clearly shown in Fig. 3 so as toclear a pillar D extending axially from the outer disk D.

Theaperture is, however, enlarged in the direction away from the fingerF beyond the amount necessary to clear the pillar D for reasons whichwill hereinafter appear. The outer disk D is cut away along the line Das seen in Fig. 3, in order to clear the contact H A 'piece ofplate-spring is provided to form a resilient finger J whose free endhasa slight projection J arranged to engage with a corresponding depressionin the finger F. The other end of this finger is pierced to receive thepillar D and is riveted thereon, but so as to be free torotate upon thepillar about the axis of rotation of the spindle.

The cam of the device is seen at K and is formed of a ring of metal thatis stamped to give the requisite cam-surface, as will readily beunderstood from the drawing.

The inner and outer disks A and D are socured to ether in any convenientmanner and the who e device is mounted on the end of the s indle C bythe aid of a single central bolt In, registering engagement beingprovided by the key B In normal operation the disks D and A and the.parts carried thereon rotate with thespindle C thus causing the wiper Gto cooperate with the stationary cam K to separate the contacts H Hperiodically in the well-known manner, -the spring-finger J serving tokeep thecontacts closed when the cam permits. It will be readily seenthat.

the oscillationsof the arm F take place about the pivot in E.

If now it is esired to inspect or obtain access to the workin surfacesof the contacts H H the resihent finger J is swung around the illar D'awayfrom the position shown in ig. 3 to the position shown in Fig. 4,whereupon .the whole arm F can be I swung about the pin E into theposition shown inv Fig. 4 thus moving from its operative position andcarrying the contact H away from in front of the contact H so that bothworking faces of the contact are readily visible and accessible. It willbe seen froman inspection of Figs. 3 and 4 that the enlargement, abovereferred to, to the central aperture of the arm F- serves to acoommodatethe resilient finger J when the "arts'are moved into the'position shownin ig, 4.. The portions of the apparatus t0 the right of the inner diskA, as viewed in the drawings, do not constitute part of the I away fromthe other in a direction parallel to the said axis of rotation, means toconnect the said moved member to the other said member so that the tworotate in unison but so that the said moved member is movable-..relatively to the other so as to carry the .contact upon it away fromthe other and expose the working faces ofboth the said consimultaneouslyto view and means normally to maintain. the said moved memberand'whereof one is periodically moved to open the contacts by carryingone of them away from the other in a direction parallel to the said axisof rotation a hinge so to connect the said moved member to the otherthat the two rotate in unison but the said moved member is movablerelatively to the other so as to carry the contact upon it away from theother and expose the working faces of both the said contactssimultaneously to view and means normally to maintain the said movedmember in the operative position, substantially as set forth.

3. In a magneto contact-breaker, the combination of two-contact-carryingmembers simultaneouslyv rotatable about the same axis and whereof one isperiodically moved to open the contacts by carrying one of them awayfrom the other in a direction parallel to the said axis of rotation, abin so to connect the said moved member to t e other that the two rotatein unison but the said moved member is movable relatively to the otherso as to carry the contact upon it away from the other and expose theworking faces of both the said contacts simultaneously to view anddisplaceable lockingmeans to maintain the said moved memberlogerativeposition, subthe other so as to carry the contact upon it away from theother and expose the working faces of both the said contactssimultaneously to view, and a resilient finger constituting theresilient control normally to hold the contacts closed supported fromthe said other member to be pivotally movable relatively. thereto aboutthe said axis of r0- ration from its normal position to one in which itpermits the said moved member to be swung away from the other about thesaid hinge, substantially as set forth.

5. In a magneto contact-breaker, the combination of twocontact-carryingmembers simultaneously rotatable about the same axis and whereof one isperiodically moved to open the contacts by carrying one of them "awayfrom the other in a direction parallel to the said axis of rotation, ahinge by which the said moved member is so connected to the l otheras tobe movable aboutan axis transverse to' the axis of rotation, and anaxial support connected to the said other member and extending through aclearance aperture in the said moved member and provided witha-resilient finger which normally bears upon the said moved member butis pivotally movable upon said support to free the moved 10 I copies ofthis patent may he obtained for five cents each, by addressing thecommissioner of ratontl,

- Washington, D. 0.

